X0306 4 2019-06-03 0 0001351288 GW PHARMACEUTICALS PLC GWPH 0001754163 Tovey Christopher J. SOVEREIGN HOUSE, VISION PARK, HISTON CAMBRIDGE X0 CB24 9BZ UNITED KINGDOM 0 1 0 0 Chief Operating Officer Ordinary Shares 2019-06-03 4 M 0 64800 3.24 A 67303 D Ordinary Shares 2019-06-03 4 S 0 64800 14.61 D 2503 D Stock Options 3.24 2019-06-03 4 M 0 64800 0.00 D 2019-02-15 2026-02-15 Ordinary Shares 64800 0 D Exercise of stock options. Following the exercise, these shares were converted into American Depositary Shares ("ADS") of the Issuer. Each ADS represents twelve ordinary shares of the Issuer. Converted from British Pounds Sterling to U.S. Dollars using currency ratio of 1.00 British Pound Sterling = 1.26 U.S. Dollars as of June 3, 2019. Represented by ADSs. The sales reported were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 20, 2019. The price reported in Column 4 is a weighted average price per ordinary share ($175.35 per ADS). These shares were sold in multiple transactions at prices ranging from $175.04 per ADS (or $14.59 per ordinary share) to $175.64 per ADS (or $14.64 per ordinary share), inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. /s/ Christopher J. Tovey 2019-06-05